1. Field of the Invention.
The present invention relates to a wiring harness, a method for producing a wiring harness and a wiring harness producing apparatus. The wiring harness may be used in internal wiring of office automation (OA) equipment, a home electric appliance or an automotive vehicle.
2. Description of the Prior Art.
A known wiring harness for electrical connection in an OA equipment, a home electric appliance or an automotive vehicle has a plurality of wires 1 bundled as shown in FIG. 16 for connecting a CPU, a display device and a variety of switches. Jigs (not shown) for holding a connector 3 and the wires 1 are arranged on a flat plate in accordance with an actual arrangement of the wiring harness. The wires 1 are arranged in accordance with the jigs, and an adhesion tape 2 for protection is wound around the bundle of wires 1. The taped wire bundle then is covered with a casing to be held in a specified configuration, and the cased wire bundle is mounted to conform to a wiring path inside an OA equipment, a home electric appliance or an automotive vehicle. However, according to this prior art, it takes a large amount of time to wind the adhesive tape 2 after arranging the wire bundle, thereby lowering work efficiency.
In view of the problem of the above described prior art, there are frequently used flat cables having a multitude of conductors. One example is a flexible print cable (FPC) in which a pattern of conductive paths 4 is printed on a flexible base film 5 which is then overlaid with a cover film 6, as shown in FIGS. 17 and 18. However, in the case of a complicated wiring harness having curved conductive paths 4, an etching mask is applied for each pattern in a production process, and after the patterns are formed in a large base film Dk, a patterned portion is punched and cut off as shown in FIG. 18. Thus, large apparatuses such as an etching apparatus and a cutting apparatus are required. Further, the use of the large base film Dk necessitates a large work space, leading to a poor space efficiency.
FIG. 19 shows another known method which includes linearly arranging a plurality of strip-like conductors 1 in parallel with each other, laying films 5, 6 on the opposite sides of the conductors 1, and folding the thus obtained flat cable according to a wiring path. According to this method, the apparatuses required for the prior art of FIGS. 17 and 18 can be dispensed with. However, in the wiring harness obtained according to the prior art of FIG. 19, folded portions 7 may be damaged or a portion between the folded portions 7 may be deformed in such a three-dimensional manner to part from the remaining parts of the wiring harness due to the elastic restoration of the folded portions 7 as shown in FIG. 20. This presents a problem that the configuration of the wiring harness cannot stably conform to the wiring path.
The respective conductors 1 may accurately be arranged along the wiring path into a corresponding configuration and at specified intervals. However, this requires a large amount of time for aligning the configuration of the conductors 1, leading to a poor time efficiency. Further, since a large film corresponding to the wiring path is required, the problem of the prior art of FIGS. 17 and 18 is left unsolved.
It is also necessary to easily cope with a design change of a wiring harness while solving the above problems. Particularly, in the case of the second prior art, the large apparatuses are forced to be changed to cope with a design change of a wiring harness, considerably increasing production cost.
An object of the present invention is to provide a wiring harness, a method for producing a wiring harness and a wiring harness producing apparatus having or allowing for a simple construction of the apparatus, which is capable of easily producing a wiring harness without folding or bending and easily coping with a design change.